This invention relates to actuating mechanisms for hand or foot activated devices and more particularly to external buttons used to actuate electromechanical switches inside of computer pointing devices such as is what is commonly called a “computer mouse” and similar devices.
Pointing devices for controlling cursor movement and entering commands into a computer are well known in the art. Pointing devices typically include some sort of positioning element, such as a rotatable ball or photonic scanner in the device or a track ball manipulated by the hand. Additionally, there are typically one or more keys or “buttons” on the input device. A computer user selects actions (i.e. provides user input to the computer) by pressing (“clicking”) a button after manipulating the positioning element. The external surface of the button and its associated internal components inside the device make up what is referred to as the button assembly.
The button assembly typically actuates an electronic switch that is electrically coupled to the computer. The button assembly usually has a spring-like character since its lever arm, usually made of molded plastic or other suitable material, is deformed when depressed by the finger, then returns to its undeformed or default position when the pressure from the finger is released. The electronic switch under the button assembly often consists of rigid plastic housing with a separate spring-loaded mechanical switch protruding from the top of the housing. When the button assembly is depressed and displaced by the force from the finger, the electronic switch moves and “clicks” when displaced the minimum required distance to actuate the switch.
A button assembly can be mechanically modeled as a plastic beam with a fulcrum on one end, this arrangement in known as a cantilever design. Many finger-actuated devices/switches on computer pointing devices employ some sort of cantilever design. However, not all computer users have the same size hand. Thus, it might be more difficult for some computer users, e.g. with short fingers, to actuate a button of a pointing device designed for users with longer fingers because their fingers do not reach sufficiently far onto the button.
Therefore, it is desirable to provide a computer pointing device with a button assembly design that accounts for differences in user hand size and strength.